This experiment was conducted to evaluate the effect of different levels of bioherbal feed supplement on the growth performances, voluntary feed intake (VFI), protein efficiency ratio (PER), lipid efficiency ratio (LER), protein productive value (PPV) , lipid productive value (LPV) and body composition of Mugil cephalus for 62 days. This study was conducted in a completely randomized design with 450 of grey mullet larvae (with average weight of 0.72±0.01g) in 5 treatments and 3 replicates (n=30 in each replicate) and included: control group without using bioherbal, other groups including: treatment 2, 3, 4 and 5. The amounts of this herbal supplement were 5, 10, 15 and 20 g/kg food. The results showed that at the end of experiment, the highest FW, DGR, VFI, PER, PPV, LER and crude protein were observed in the diet containing 15 g /kg bioherbal supplement in all of these parameters. Furthermore treatment 4 (15 g/kg) showed a significant difference compared with control treatment (P<0.05). Finally, the present results suggest that diet containing 15 g/kg bioherbal supplement (ginger and fennel powder) could improve growth, feed performances and carcase quality of Mugil cephalus larvae.